Yes in theory... (I had a pretty cool tail as part of a costume I made really. And it seemed about right in terms of size, though maybe it'd be more interesting if it was slightly bushier. Holo from Spice & Wolf comes to mind here.)
The problem with this though is that in reality, biology dictates if humans had tails they'd be pretty ugly.
Why, you ask? Because our closest relatives with tails are monkeys. And we are mostly hairless.
So imagine having a huge monkey's tail (remember proportions here. A typical tail is longer than the body of the animal it's attached to)
But... Without any hair on it. I can't imagine that looking all that appealing. (Cats are cute right? Well have you ever seen what a hairless cat looks like? >_>)
But, I liked my costume tail enough that if it were properly attached and I could actually move it that'd be pretty cool.
So... Yes, if I get to choose what kind of tail.
No if it relates in any way to normal human biology or evolution.